It is c. White blood cells
Variations are beneficial for the survival of the species. Populations of organisms fill well-defined places, or niches, in the ecosystem, using their ability to reproduce.However, if some variations were to be present in a few individuals in these populations, there would be some chance for them to survive.
Answer: The SA node
Answer choices are:
<span>A. </span>The AV node
<span>B. </span>The SA node
<span>C. </span>The purkinje fibers
<span>D. </span>The AV bundle
The SA node<span> is the heart's natural pacemaker consisting of a cluster of cells located in the upper part of the wall of the right atrium. (the right upper chamber of the heart). The electrical impulses are produced and sent out from there to regulate heartbeat. This is also called the sinus code. </span>
The correct option from given options is "b", that is <span> it changed ideas about which animals were closely related.
</span>Cladistics<span> was </span>invented for the purpose of improving on taxonomy and it is a way to deal with biological classification. DNA technology lead to more use of cladistics because it changed ideas about which animals were closely related and also it showed new evolutionary relationships between animals.
Answer:
C.22 grams because mass cannot be created or destroyed
Explanation:
Reaction equation:
2H₂ + O₂ → 2 H₂O
Mass of oxygen = 18g
Mass of hydrogen = 4g
The mass of water produced is 22g according to law of conservation of mass.
The law states that " in a chemical reaction, mass is always conserved"
The sum of the mass of product and reactants must always be the same.